Reducing coolant hose diameter?

[3d914]

I'm gathering data for my 914-SHO conversion about getting the coolant from the front to the mid-engine position. The fitting sizes on the engine appear to 1-1/4" for inlet and 1-1/2" for outlet.

I don't have the fitting sizes on the radiator - you think they'd match, but that's not a given. I'd like to get the sizes for the single-pass and double pass radiator if different. Anyone track that info?

I'd like to get the supply hose down to 1" and the return to 1-1/4" to make routing along the body easier.

Any thoughts, experiences?

TIA,

 

[Off Road SHO]

Gerard! You're still at it! Great to hear. You can make either hose (pipe) 1"-1.5" and it won't matter too much. I always liked the suction side of water pumps to be able to suck easily so I'd do a 1.5 from the radiator(s) to the pumps's inlet.

The thermostat really necks down the flow to the radiator so a 1" should be plenty. Make it out of finned copper tubing from heat exchangers and you won't need a radiator (almost).

Good to see you back at it. I've started a SHO powered LoCost and am moving at a snail's pace, but moving.

Tom

 

[3d914]

Tom,

Thanks for the input. Glad to hear you're still doing the Locost. Hope you plan to post some pictures along the way. I just saw the video of your sand rail in action. Dang, I feel sorry for the suckers riding in the wake of that thing - cough, cough!!

Do you have the dimensions on the stock radiator and hose connection sizes? One option I'm looking at is to split the one radiator (by volume) into two and mount them in the rear wheel well in front of the flares.

The stock radiator is a single-pass, right? Does it have single or dual fans?

TIA,

 

[Ocnaj]

Someone correct me if I'm wrong but I'm pretty sure MTXs are single-core with a single fan and ATXs are dual-core with dual fans.

Not sure on the dimensions.

 

[rbruso]

But even the dual core radiators are still single pass. One hose at top driver's side, the other at bottom passenger's side.

 

[3d914]

Thanks guys.
Did some more digging and found the following for after-market single-core radiator:
Inlet size = 1-1/2" (at top-left as per Bruso)
Outlet size = 1-1/2" (at bottom-right as per Bruso)
Core size = 24" x 15" x 1"
Surface area = 360 in.sq.

If someone could confirm these for stock MTX/ATX that would be great.

 

[rbruso]

Thanks guys.
Did some more digging and found the following for after-market single-core radiator:
Inlet size = 1-1/2" (at top-left as per Bruso)
Outlet size = 1-1/2" (at bottom-right as per Bruso)
Core size = 24" x 15" x 1"
Surface area = 360 in.sq.

If someone could confirm these for stock MTX/ATX that would be great.

Just measured my spare hoses. Both hoses are about 1 1/2".

The 24 x 15 looks correct.

This is an '89, so MTX. My dual core radiator is about 2" thick, which makes sense.

 

[3d914]

Thanks bruso, that's a big help.

 

[3d914]

I've been considering my install options for the radiator. The stock SHO radiator will fit with no problems, and I can mount in the front trunk of the 914 as do the subi & V8 guys. However, the main draw-back is routing the coolant hoses back to the engine (behind the driver) and venting the heated air out of the front trunk. I really don't like hacking big sections out the wheel wells to vent air. Better, but still not ideal, is venting through the hood.

As an alternative I've been considering a couple different paths:

1. Mount two 8"x18" radiators in the fender wells, and a third under the rear trunk on the drivers side.
2. Mount two larger 11"x20" under the trunk on both sides.

Option 1 would require an air inlet vent on each side, fabbed out of fiberglass, with metal or FG housing to direct the air into the radiators. The third radiator would simply draw air from the engine bay & under the car and vent back out the rear. The side vents would add a certain "coolness" factor since the car has flares.
Here's some sample radiators.

Option 2 would be the most stealthy. I know guys who have mounted oil coolers this size with fans, so I'm reasonably confident this could work. Another option on the location would be up next to the firewall, but laying almost flat - drawing air up from underneath the car and venting up.
Larger one.

Thoughts?

 

[rbruso]

My only thought on under car mounting is rocks, especially if you're on dirt roads a lot.

Side scoops to twin radiators would blow the stealth factor, but it doesn't look like that's a concern for you

 

[3d914]

bruso, if the spot I'm hoping will work, it will be better than Opt-2 because it will be forward of the rear wheels - just behind the firewall. I'm thinking that a radiator on each side of the engine bay, slightly behind the firewall. Since I've removed the shelf used for the flat 4's, 6's, & 8's it provides quite a bit of space.

I'm hoping to mock up something here before the end of the month, but got some welding to finish first.